Garnish with a slice of lemon, or with fruit peel or juniper berries, depending on the specific botanicals of each gin. If you choose to use the zest, first squeeze it over the glass to release the essential oils. Then it's ready to be served.
Gin and tonic has medical origins and is the result of the meeting of different cultures. Gin was created in 1650 at the University of Leiden by Dr. Sylviu as a 'potion' capable of releasing the beneficial effects that juniper berries have on the blood. The tonic water, in its primordial form, comes from the Cinchona tree. Native Americans extracted it and used it to treat fever. Sharing the secret with the Spanish colonists, they began to use it against malaria. But we have to wait until the end of 1700 when the German chemist Schweppe added carbon dioxide and sugar to the tonic, giving life to soda.
And when the gin and tonic landed in India in the 18th century together with the British, it didn't take long for lime to be added to the drink.
More than variations of the cocktail, it would be correct to speak of the different gins. There are different types, such as London dry gin, distilled gin or compound gin. Depending on the distillation method, the result changes. There are drier gins, more fragrant gins and others with a more juniper flavour, others citrus or floral - there is something for all tastes. There are also different types of tonics and depending on which one you choose, the flavour of the cocktail varies. Indian tonic goes well with any type of gin, but if you prefer a drier cocktail then you can opt for a dry bitter tonic. In any case, it is recommended, being a cocktail with only two ingredients, to choose high-quality products to obtain a better result.
The ratio of the two ingredients can vary. According to the Italian tradition, gin tonic was considered an after-dinner cocktail and prepared with 1 dose of gin and 2 of tonic. Recently the trend, deriving from the Iberian peninsula, is to drink it as an aperitif, therefore prepared with 1 dose of gin and 3 of tonic, which is less alcoholic.